A wireless tag such as an RFID tag, which includes an IC chip storing therein information and an antenna unit, executes transmission and reception of data with a reader/writer, owing to wireless communication utilizing an electromagnetic wave. The technique of the wireless tag is used in many fields such as the distribution of goods, commodity management, and security.
The wireless tags are attached on article serving as targets or joined thereto using strings, and used for inventory management for the articles, or the like. As an example of the application of the wireless tag, there is an ID label detecting that the ID label has been peeled from an identification target object. This ID label is used for a security application for detecting the presence or absence of the opening of packing or a container, or the like. In addition, a technique has also been proposed where a wireless tag in which a portion (feeding line) of an antenna is disconnected owing to the opening of packing or a container is used and, on the basis of whether or not it is possible to communicate with the corresponding wireless tag, the presence or absence of the opening of the packing or the container is determined. For example, these technique are disclosed in Japanese Laid-open Patent Publication No. 2001-13874 and Japanese Laid-open Patent Publication No. 2009-251942.